Determination of position location can be important for many different types of equipment, particularly for mobile terminals. For example, determination of position location can allow the user of the mobile terminals to ascertain the user's whereabouts, enabling the user to make appropriate navigation or other decisions. In addition, when provided to a third party, information regarding position location of mobile terminals can enable the third party to locate and provide assistance or render service to the user.
There are several positioning technologies which can be used to determine the position of mobile terminals. They are Observed Time Difference of Arrival (OTDOA) positioning, Assisted Global Positioning System (A-GPS) positioning, and fingerprinting positioning etc. Among these positioning technologies, fingerprinting positioning technology is now widely used and also discussed during 3GPP standardization.
Also known as Radio Pattern Matching or Radio Signature, fingerprinting technology represents a family of path loss based technologies that rely on matching the RF environment (as experienced by the mobile terminals) to the known characteristics of the larger RF system in which the mobile terminals are operating. Whenever a position request arrives, a radio fingerprint is first measured, after which the corresponding grid points with similar characteristic are looked up and a location estimate is calculated and reported. The fingerprint may e.g. consist of                The cell Ids that are detected by the terminal, in each grid point;        Quantized path loss or signal strength measurements, with respect to multiple radio base stations, performed by the terminal, in each grid point;        Quantized Round Trip Time (RTT, in WCDMA) or Timing Advance (TA, in GSM and LTE) or UE Rx-Tx time difference (in LTE) in each grid point;        Quantized noise rise, representing the load of a CDMA system, in each grid point;        Quantized signal quality;        Radio connection information like the radio access bearer (RAB);        Quantized time.        
It can be seen, fingerprinting positioning technology requires a large number of field measurements, together with simulated measurements, for being used as reference inputs. Such measurements require a remarkable capacity for storage which increases cost and lowers look-up efficiency. Besides fingerprinting positioning, other positioning technologies may face similar problems.